Keyboard



May 14, 1940.

L. M; POTTS KEYBOARD Original Filed Jan. 17, 1929 2 Sheets-Sheet lINVENTOR. LOUIS M POTTS ATTORNEY.

Patented May 14, 1940 KEYBOARD Louis M. Potts, Evanston, Ill., assignorto Teletype Corporation, Chicago, 111., a corporation of DelawareOriginal application January 17, 1929, Serial No. 333,161. Divided andthis application October 12, 1938, Serial No. 234,566

3 Claims.

The present invention relates to telegraph systems and apparatus andmore particularly to apparatus for the transmission of groups of signalimpulses indicative of stock items and quotations.

The present application is a division of application Serial No. 333,161,filed January 17, 1929.

An object of the invention is a transmitter for the transmission ofgroups of signal elements, which may be operated at high speeds withoutsignal interference.

A feature of the invention is a transmitter arranged with a plurality ofkey sections which are operated sequentially and in a definite order forthe transmission of groups of Signal elements.

'A further feature of the invention is a telegraph transmitter whereinoperation of its key levers is determined cyclically in response to asignal distributor with which it is operatively associated.

' The above and other objects and features of the invention areaccomplished by the provision of a keyboard With its'key levers arrangedin a plurality of groups or sections. Individual to each group orsection are a plurality of contacts which, through the depression of therespective key levers, are operated permutably in accordance with theparticular code identified with the several key levers. Different signalconditions such as, for example, the first, second, and third letters ofa stock abbreviation, the units, tens, hundreds, and fractions part ofthe stock quotation, and the range thereof; that is, whether it be alow, high, last, or close quotation, are allocated to the varioussections of the keyboard.

Each keyboard section is provided with a self locking apparatus which isnot released until a predetermined interval during the transmission atwhich time a particular signal corresponding to said section has beentransmitted Transmission of the groups of signal impulses, as determinedby the operation of the contacts of the several sections of the keyboardis achieved through the operation of a start-stop distributor initiatedin its operation through the closure of a contact associated with thesection of the keyboard allocated to the fractions part of the quotationso that not until the stock item and its quotation have been set up onthe various keyboard sections will a condition be established for therelease of the distributor. During the cycle of rotation of thedistributor, all of the groups of impulses identifying the stock item,its quotation, and range, will be transmitted.

A better understanding of the invention may be had from the followingdescription, taken in conjunction with the accompanying drawings,'wherein Fig. 1 is a circuit. diagram of the keyboard transmitter anddistributor;

Fig. 2 is a detail view of a section of the keyboard showing the keylevers in their normal position;

Fig. 3 is a detail view of a section of the keyboard showing a key leverdepressed and locked in its depressed position;

Fig. 4 is a detail view of the keyboard unlocking mechanism;

Fig. 5 is a partial plan view of the keyboard; and

Fig. 6 illustrates the code combinations which may be utilized in thetransmission of stock items, stock quotations, and quotation ranges.

As disclosed in Fig. 1, thekeyboard includes eight different sectionsindicated generally by the reference characters H], II, 12, I3, I4, l5,l6, and I l. Each of the sections l0, II, and 12 comprises a set oftelegraph key levers it, one for each letter of the alphabet. Includedin each of the sections l3, l4, and iii are ten key levers it, one foreach, of the digits 0 to 9. Keyboard section l6 includes seven keylevers 20, one for each of the fractions part of a quotation to and ablank key lever 2| for establishing a starting condition for thedistributor, as will be subsequently described. Keyboard section I!includes four key levers 22, 23, 24, and 25, one each for the closing,open, high, and low range quotations, respectively.

According to the illustrated embodiment, the key levers i8 of thekeyboard section Hi selectively operate five contactors 2B, 29, 30, 3|,and 3?. permutably in accordance with the particular key lever of thekeyboard section which is de pressed; that is, upon the depression ofthe various key levers, a different permuted setting of the contactors2&32 will be established. 0011- tactors 28-.-32 are arranged to engageeither upper contacts 34 or lower contacts 35, depending upon theoperation of the key levers. Normally, the contactors engage thecontacts 36. All of the contacts 34 as well as all of the contacts 35are connected in multiple to sources of negative and positive currents,respectively. Upon the depression of a key lever 18, the contactors 2832will be operated permutably to apply to their individual conductorscurrent of polarity determined by the position of the contactors.

The key levers of the second and third sections of the keyboard; namely,H and I2, control five contactors similar to those described for thefirst keyboard section which is indicated generally by the numeral H].In a manner similar to that described for the section in of thekeyboard, the contactors of the sections H and I2 will be operatedpermutably for controlling the potential applied to the conductorsindividual thereto.

The levers 19 on the fourth section of the keyboard or the sectionnumbered 13, comprising the ten digits, selectively control fourcontactors 3B W keyboard. andnormally under. the, tension. of

- zontal section lfi.

zontal section Mlextends. adistance insufficient normally to'engage. auniversal member 4?...of.;a

condition identified with the range selection 7 which is efi'ective atthe connected receiving station .to determine the indicators oi.aselected group of;-indicators to be operated-throughtthe mechanismprovided for that purpose.

Upon operation of .a .-.k.ey r'lever such as, "for example,I6,.insectionJ-ll-of the keyboard, a-locking mechanism functionsto-lockthe key-lever in its .depressed position and lock; therremaining keylevers in the section against operation. As shown particularlyin Figs. 2and 3,, the. .key levers. .such as, for example, i8, are pivotallymounted on rod All which extendstransversely. of the keyboard and whichis suitably secured to-the frame thereof. Each of thekey levers isprovided-with down- Wardly projecting lugs A! on the=underysurfacethereof. .These lugs. are arranged invarious-combinations on therespectivezkey. levers so thatfor theseveral key levers .adifferentsignal condition,

.upon its depression,.will.-be established. The lugs M on theundersurface ofthe.key ..levers cooper- ...ate .with. levers .42, pivotedonrods 43 ;..that.is, .there :isa rod 43 individual to. each'of.the-levers .42 and thereis a lever 42 for ,each .of .the. possible.five

, projections L 4 l on the. underside of. the .-key, levers l8. Inresponseto the operation. ofea .keylever, the, lever-s42 will .berotatedin a,counterclockwise direction, has viewed in Jig. ..,2,...tocausecorresponding operation of contactors..28.32 .to-,disengage contact-34 and. vengage .contact 35 in accordance with the projections AI.

As ;.specifically .disclosediinFig. .-2,,key. lever l.8.has,. on itsunder surface .two .projectionsA l Consequently,

vupon its -depression,,.the .levers-42. associated-withsuchprojectionswill .be-operated for causing the contactors l .and. Sitedisengage their. contact 34 andrengage their .contact.35 for-applying.to..the

.- conductor ,individuahthereto the .polarityof the sourceof currenttouwhichit is connected.

Extending upwardly from each of the key levers l8 isa curved lugmember.55 provided with ahori- As .shownin Fig. .thehorilocking lever .48whenallof therkeylevers [.8 are intheirunoperated position. Lever. as is.pivoted uponla rod .49 suitably. mounted in. the, frame .of

a spring 56 which has one end securedtolever .48 andtlie other endsecured to .a.spring post. .on the vframe ofthe keyboard. AlsoasshowninFig. 2, the-universal member A! 'is adjacent :the lug memberson each of. the key levers.

Springfifi normallymaintainslever 48 incri- -.gagement,with a latchleverfil pivotally mounted .on a rod .52 suitably carried in the-frameand normally urged into engagementwith the locking lever. is by theaction .of spring-.53, one end of Which-is secured to an extension onthe latch lever ,l'ahand the other end of .which-is securedto a-springpost mounted in the frame.

Latch lever 5| hasan extension 54 on which. is mounteda universal member55 extending beneath all of the key; levers l8.

Under normal conditions with all of the key levers of that section in anondepressed position,

spring 53 maintains the universal member 55 in engagement with the lowerside of all of the key levers I8. 'zengagement with lever 68 and actsagainst the itension of spring '58 to maintain the universal 1 In thatposition, latch lever 5! is in member il -out of engagement with thehorizontal extension 136 of the lug member @Eof each of the key levers68. Upon the depression of any of *these key levers, the universalmember 55 is rotated in a counterclockwise direction, as viewedinFigJ-Z, to the position shown in Fig. 3. Under such-conditions, latchlever-5i is rocked against the tension of spring fitauntil itdisengagesolever 48. 7 Spring 53 thereupon rocks lever 48 in .acounterclockwise: direction about rod- 49 .tomove the universal memberE1 to the position shown-in extension MS- of the lug member .155 onthedepressed key lever 18. The .nondepressed key levers ill and thedepressed key leverlS will be locked in. they nondepressed anddepressedpositions', respectively, by the universal member. 41

occupying a positionas shown in Fig.3. .Ihthe case of the depressedkeylever, .the...universal member 4'5 will engage. the .uppersurfaceofhorizontal extension 55, whereas for the .nondepressed Z20 .Fig. 3.-inoperative relation with the horizontal key levers the universal memberi! will. engage.

the under surface of thehorizontal extensionfit .of the nondepressed keylevers.

Restoration of acdepressed key lever .to its normal or unactuatedposition is controlledby an.

electromagnet 5?, shown ,in; detail in Figs. 4-and 5, anddiagrammatically in Fig. 1. Asshownin Figs. 4 and 5, the armature-.58 ofthe electromagnet 5'1 is secured to a pin 59 which is journaledin sideplate 60 constituting apart .oflthe keyboard Secured to. the oppositeendof pin 59 is .a .lever B! fastened to the universal member ill.-Whentheelectromagnet 51 is energized, itsarmaframe.

ture is attracted to the dottedlineposition shown in Fig. 4, and lever{58 is rotatedin a clockwise direction against the action ofispringfifiito. move universal memberJllyfree of thehorizontal extensions 46 on thelug member 45 ofeach oithekey levers I8. Spring53 thereupon restoreslevertl' to the position shown in. Fig. 2 and likewisethe depressed keyleverwill be restored. to itsnormal or unactuated position.

Referring now to Fig. -1, it will be notedthat each of theco11tactors--23-.-.32. is connectedbya conductor such as 55 individualthereto to individual segments of astart-stop distributor. 66,

whichcomprises a plurality of groups of seg- :ments 5?, 68, 69, 10,1!,"12, .l3,.and Mora group. of'segments individual to..each of. thesections of thekeyboard indicated generally bythe reference numeralilk-I1. Of course, as is custome ary, the distributor 66 includes intheringwith the respective groups of segments 6!.14,. astop segment anda start segment numbered 15 .and

315, respectively. ,Distributor :68. also includes. a

solid ring ll arrangedto be bridged with the ring including therespective groups of segments by electrically interconnected'b-rushes l8and 19 which are secured to a brush arm 80. .Brush arm 86 normally tendsto rotate by power comfrom a motor 82 which maybe. supplied with anysuitable source of power and is normally held against rotation .by thearmature v ,of anelectromagnet 83.

-70 municated thereto through .a frictioniclutch 8| 85-432 of theadjacent ring of the distributor.

As also shown in Fig. l, the solid ring 11 of the distributor isconnected to a line conductor '95 extending to a distant receivingstation where apparatus responsive to the signal impulses generatedthrough the operation of the distributor under the control of therespective sections of the keyboard may be located.

Segment l5 connected to the negative side of battery acts as the stopsegment, whereas segment 16 connected to the positive side of batteryserves as the start segment. The next fifteen segments or the segmentsincluded in the groups 61, 68, and 69 are connected to the fifteencontactors 28-32 of the sections H], H, and I2 of the keyboard. Thesucceeding twelve segments or the segments included in the groups H3, H,and F2 are connected to the contactors 3B operated by the key'levers ofthe sections I3, 14, and I5 of the keyboard. The next three segments orthe segments included in group 13 are connected to the contactors ofsection l6 of the keyboard and the next four segments or the segmentsincluded in group M are connected to the contactors controlled by thekey levers in section I! of the keyboard.

By the arrangement previously described, there is transmitted for eachrotation of the distributor 65, three letter characters, three numbers,a fraction, and a range signal. It will be noted that the samecombination of impulses may be used for a letter, for a number, and fora fraction, due to the fact that the position of the combination isdetermined with respect to the start impulse as allocated to aparticular position in the cycle of rotation of distributor 66.

As disclosed in Fig. 1, the segments 85-432 are positioned with respectto the groups of segments 1--'M, so that following the passage of brush19 over the last segment in the respective groups of segments, brush 93will engage a segment 85-92 to connect positive battery to the windingof the unlocking magnet 51 of the respective sections of the keyboard.Consequently, as the distributor brush arm 80 progresses in its cycle ofrotation, the key levers of the respective sections previously depressedwill be released and the contactors controlled thereby will be restoredto their normal or unactuated position, following which another keylever may be depressed for utilization in a subsequent cycle of rotationof distributor 66.

The section of the keyboard indicated generally by the numeral Itincludes mechanism whereby, upon the depression of any of the key levers26, a contact 96 will be closed. This contact is connected to ground,and when closed, completes a circuit over conductor 91 through thewinding of electromagnet 83 to grounded battery. Consequently, upon thecompletion of the noted circuit, electromagnet 83 will be en ergized tomove its armature out of the path of brush arm Bii, which, as previouslydescribed, normally tends to rotate by power communicated thereto from amotor 82 through a friction clutch 8!. The brush arm 80 rotates and indoing so, the brushes l8 and I9 and 920 and 93 carried by the brush arm89 pass over the respective segmented and solid rings for performingtheir allocated function. The brush arm will complete a cycle ofrotation when its rotation will. again be arrested by its engagementwith the armature of electromagnet 82, in which position it will bemaintained until a key lever of the section It of the keyboard isdepressed, when the operation just described will be repeated.

It is significant to note that the previous description of the keyboardlocking mechanism applied specifically to section In of the keyboard,

whereas the same mechanism is applied to each section of the keyboardand functions in a manner identical to that described in connection withsection ill of the keyboard.

In order to transmit annotation of a particular stock item. the operatorfirst depresses a key in each of the first three sections 10, ll, and I2of the keyboard, assuming that the stock item includes in itsabbreviation three letters. However, if the stock item includes only twoletters in its abbreviation, a key in each of the first two sections;namely, l0 and H, of the keyboard will be depressed. If a key in sectionI2 is not depressed, a blank signal for that particular section of thekeyboard will be transmitted through the operation of the distributor66. Due to the depression of a key in each of the sections IO, M, and12, a code identified with the letters of the alphabet, as indicated inthe first three columns of Fig. 6, will be transmitted through theoperation of distributor 66.

The operator will also depress a kel in each of the sections it, id, id,and 56 which will set up conditions indicative of the codes for theunits, tens, hundreds, and fractions part of the quotation. Aspreviously described, the depression of a key in section I6 causes theoperation of contact 98 which completes a circuit from ground at batterythrough the winding of electromagnet 83, conductor 9i, and contact 96 toground. Electromagnet 83 is thereupon energized and withdraws itsarmature from engagement with brush arm 80, which rotates by powercommunicated from motor 82 through friction clutch Bi.

With brush l9 resting on segment 15, current from the negative pole ofthe source of current connected to segment 15 will flow over lineconductor 95, which is connected to solid ring 1'! of distributor 56. Asthe brush [9 moves to the next or start segment it, positive battery isconnected to line 95 through brushes 18 and I8 and solid ring H. Theapplication of the start impulse to line conductor will cause tributorat the receiving or distant station to begin its rotation, for suchdistributor, like distributor 68, has a brush arm normally held againstrotation by the armature of a normally lie-energized start magnet.energizes the start magnet of the receiving distributor at the distantstation and permits rotation of its brush arm which will rotate in timedrelation with brush arm 89 of distributor 6B.

As the brushes 1'8 and five segments or the segments included in group67, a code is impressed upon line conductor 95 in accordance with theposition of the contactors 28-32 of section iii of the keyboard. Theimpulses will be transmitted irorn the positive and negative sources ofcurrent connected to contacts 34 and. 35, as previously described.

As the brushes "#8 and 79 continue their rotation, engagement with thesegments of groups 68 the receiving dis- The start impulse #9 pass overthe first and 69 will be effected sequentially and a code .for,-,each ofthe-notedgroups of'segmentsfitand 569- Will be transmitted over theline-conductor '95,as determined by the position of the contact-oreunder the control of key levers in the sections H and 52 of thekeyboard. The code impulses transmitted as a result of the passage ofthe brushes 2'3 and 19 over the group of segments iii, 65, and 69 willbe efiective at the receiving station to select an indicator allocated.to the three groups of code signals transmitted.

Thebrushes-lt and I9, in passing over thenext four segments or thesegments included inggroup .iii. transmit a'code signal-comprising acombination of four impulses individual. to a digit such as, forexample, the hundreds part of a quotation for the particular itemselected through the operation of keys in the sections it), i i, and 42.

The impulses so transmitted will function to operate correspondingly theindicator at the distant receiving station selected through theoperation of the key levers in sections Ii], H, and

82. Similar operation occurs as the brushes 18 and'ivi pass over thesegments included in groups ii, 32, and 73. Code signals dependent uponthe the stock items.

depression of particular keys of the sections Hi,

15, and it of the keyboard will accordingly be transmitted.

It was noted previously that section I? of the keyboard includes keylevers 22, 23, 2t, and 25,

which are identified with the range of the quotation; that is, the keylevers may be identified with the open, high, low and last quotations oftransmitted in accordance with the depression of any of the key levers22-25 will controhat the receiving or distant station, mechanism forselecting an indicator identified with the class of the quotation; thatis, for each of the stock items there may be four indicators, an open,high, low, and last indicator. The code signal transmitted as thebrushes i8 and 19 pass over the group of segments it will select one ofthe named indicators on which the hundreds, tens, units, and

fractions part of the quotation will be displayed, as determined by theoperation of the key levers of sections is, M, 5, and N5 of thekeyboard.

rushes 929 and 93, which are also mounted on brush arm 3i rot-ate withbrushes 18 and 19.

Brush 83 successively engages segments 85-432 and connects such segmentselectrically with solid as shown,'is connected to the posof battery.Upon the engagement ring 8d which, itive terminal of'brush 3 with thesegments 8592, a circuit for the respective locking magnets of therespective sections of the keyboard is established; for

example, when brush 93 engages segment 95, a

energizing the unlocking vmagnet 5? of section ii) of the keyboard.Eleccircuit is completed for troznagnet 5?, in operating, moves lever 49in a clockwise direction against the tension of spring 53- to restoreuniversal member Q! and lever 5! to the position shown in Fig. 2. Undersuch conditions the depressed key lever I8 will be restored toits-normal or unactuated position. The operator may then operate any ofthe keys in section it of the keyboard.

As the brush 93 successively engages segments 8692, the unlockingmagnets 51 identified with the other sections of the keyboard'will beoperated sequentially to restore the keyboard sections ,to. norma1.Folowing the operation of the unlocking magnet 57 of each of thesections of the keyboard, another or thesame key lever in such In otherwords, a code signal section or sections:maybedepressed. .The brush arm88 of the distributor -66 continues its'rotation until itagain engagesthe-armature of electromagnet 83, where it will beheld until a subse-'quent operation of a key lever in section 56 when contact 85 will againbe operated to complete the energizing circuit for electromagnet 83toagain release brush arm to of the distributor 66 for ro-. ,tation.

'IIhe various code signals for the parts of the quotation and the open,high, low, last, or close ..quotations are shown in Fig. 6., It ismanifest, however, that other codes might be developed. for

identifying-the various letters of. the stock items and the quotations.

According to the foregoing description, the invention embodiesaplurality of keyboard sections each including a plurality of key leversfor op-. .erating a plurality of contacts permutably dependent uponthe'group of signals identified with a character to be transmitted. Uponthe depression of a key lever inthe respective sections, of t thekeyboard, the key levers ofthe actuated section are held or lockedagainst depression. Successive sections of a segmented ring of astartstop distributor are connected successively'to the severalgroups'of contacts of thevarious sections of the keyboard which, uponthe depression of, a

key lever in one of the sections of the keyboard,

1. In a telegraph transmitter, a series of key levers, a lock-forholdingthekey levers in operated and unoperated position upon theoperation .of a key lever, a latch normally holding the lock in freeposition, means to release the latch upon the operation of any keylever, and remotely con trolledineahs to relatch theylock.

2. In a telegraph transmission system, a plu rality of keyboards,keyboardlatching apparatus adapted to store a plurality of signalssuccessively transmitted by said keyboardsrmeans'toinitiate transmissionunder a predetermined condition of said apparatus, means to storesignals of av sec- 0nd group insaid apparatus before the signal of apreceding group has been completely transmitted, and means to delay thestorage of a sec-. ond group of signals until the corresponding group ofsignals 'of a first group has been'transmitted.

3. In a telegraph system, a signal storage device adapted to receiveand-store groups of permutation code signals for transmission-succes-fsively, a start-stop transmitter fortransmitting the signals stored insaid storage device, means to initiate said transmitter after saidstorage device has been predeterminedly conditioned, means to begin thestorage of a succeeding group'of signals in said storage device before apreceding group of signals has been completely transmitted, and means todelay the storage of a succeeding group of signals until thecorresponding signals of a preceding group have been transmitted.

LOUIS M. PO'I'I'S.

